xref: /linux/drivers/irqchip/irq-ath79-misc.c (revision 33efa7dbabcf62491c2eac9631752d52b8e159f8)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *  Atheros AR71xx/AR724x/AR913x MISC interrupt controller
4  *
5  *  Copyright (C) 2015 Alban Bedel <albeu@free.fr>
6  *  Copyright (C) 2010-2011 Jaiganesh Narayanan <jnarayanan@atheros.com>
7  *  Copyright (C) 2008-2011 Gabor Juhos <juhosg@openwrt.org>
8  *  Copyright (C) 2008 Imre Kaloz <kaloz@openwrt.org>
9  *
10  *  Parts of this file are based on Atheros' 2.6.15/2.6.31 BSP
11  */
12 
13 #include <linux/irqchip.h>
14 #include <linux/irqchip/chained_irq.h>
15 #include <linux/of_address.h>
16 #include <linux/of_irq.h>
17 
18 #include <asm/time.h>
19 
20 #define AR71XX_RESET_REG_MISC_INT_STATUS	0
21 #define AR71XX_RESET_REG_MISC_INT_ENABLE	4
22 
23 #define ATH79_MISC_IRQ_COUNT			32
24 #define ATH79_MISC_PERF_IRQ			5
25 
26 static int ath79_perfcount_irq;
27 
get_c0_perfcount_int(void)28 int get_c0_perfcount_int(void)
29 {
30 	return ath79_perfcount_irq;
31 }
32 EXPORT_SYMBOL_GPL(get_c0_perfcount_int);
33 
ath79_misc_irq_handler(struct irq_desc * desc)34 static void ath79_misc_irq_handler(struct irq_desc *desc)
35 {
36 	struct irq_domain *domain = irq_desc_get_handler_data(desc);
37 	struct irq_chip *chip = irq_desc_get_chip(desc);
38 	void __iomem *base = domain->host_data;
39 	u32 pending;
40 
41 	chained_irq_enter(chip, desc);
42 
43 	pending = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS) &
44 		  __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
45 
46 	if (!pending) {
47 		spurious_interrupt();
48 		chained_irq_exit(chip, desc);
49 		return;
50 	}
51 
52 	while (pending) {
53 		int bit = __ffs(pending);
54 
55 		generic_handle_domain_irq(domain, bit);
56 		pending &= ~BIT(bit);
57 	}
58 
59 	chained_irq_exit(chip, desc);
60 }
61 
ar71xx_misc_irq_unmask(struct irq_data * d)62 static void ar71xx_misc_irq_unmask(struct irq_data *d)
63 {
64 	void __iomem *base = irq_data_get_irq_chip_data(d);
65 	unsigned int irq = d->hwirq;
66 	u32 t;
67 
68 	t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
69 	__raw_writel(t | BIT(irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
70 
71 	/* flush write */
72 	__raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
73 }
74 
ar71xx_misc_irq_mask(struct irq_data * d)75 static void ar71xx_misc_irq_mask(struct irq_data *d)
76 {
77 	void __iomem *base = irq_data_get_irq_chip_data(d);
78 	unsigned int irq = d->hwirq;
79 	u32 t;
80 
81 	t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
82 	__raw_writel(t & ~BIT(irq), base + AR71XX_RESET_REG_MISC_INT_ENABLE);
83 
84 	/* flush write */
85 	__raw_readl(base + AR71XX_RESET_REG_MISC_INT_ENABLE);
86 }
87 
ar724x_misc_irq_ack(struct irq_data * d)88 static void ar724x_misc_irq_ack(struct irq_data *d)
89 {
90 	void __iomem *base = irq_data_get_irq_chip_data(d);
91 	unsigned int irq = d->hwirq;
92 	u32 t;
93 
94 	t = __raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
95 	__raw_writel(t & ~BIT(irq), base + AR71XX_RESET_REG_MISC_INT_STATUS);
96 
97 	/* flush write */
98 	__raw_readl(base + AR71XX_RESET_REG_MISC_INT_STATUS);
99 }
100 
101 static struct irq_chip ath79_misc_irq_chip = {
102 	.name		= "MISC",
103 	.irq_unmask	= ar71xx_misc_irq_unmask,
104 	.irq_mask	= ar71xx_misc_irq_mask,
105 };
106 
misc_map(struct irq_domain * d,unsigned int irq,irq_hw_number_t hw)107 static int misc_map(struct irq_domain *d, unsigned int irq, irq_hw_number_t hw)
108 {
109 	irq_set_chip_and_handler(irq, &ath79_misc_irq_chip, handle_level_irq);
110 	irq_set_chip_data(irq, d->host_data);
111 	return 0;
112 }
113 
114 static const struct irq_domain_ops misc_irq_domain_ops = {
115 	.xlate = irq_domain_xlate_onecell,
116 	.map = misc_map,
117 };
118 
ath79_misc_intc_domain_init(struct irq_domain * domain,int irq)119 static void __init ath79_misc_intc_domain_init(
120 	struct irq_domain *domain, int irq)
121 {
122 	void __iomem *base = domain->host_data;
123 
124 	ath79_perfcount_irq = irq_create_mapping(domain, ATH79_MISC_PERF_IRQ);
125 
126 	/* Disable and clear all interrupts */
127 	__raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_ENABLE);
128 	__raw_writel(0, base + AR71XX_RESET_REG_MISC_INT_STATUS);
129 
130 	irq_set_chained_handler_and_data(irq, ath79_misc_irq_handler, domain);
131 }
132 
ath79_misc_intc_of_init(struct device_node * node,struct device_node * parent)133 static int __init ath79_misc_intc_of_init(
134 	struct device_node *node, struct device_node *parent)
135 {
136 	struct irq_domain *domain;
137 	void __iomem *base;
138 	int irq;
139 
140 	irq = irq_of_parse_and_map(node, 0);
141 	if (!irq) {
142 		pr_err("Failed to get MISC IRQ\n");
143 		return -EINVAL;
144 	}
145 
146 	base = of_iomap(node, 0);
147 	if (!base) {
148 		pr_err("Failed to get MISC IRQ registers\n");
149 		return -ENOMEM;
150 	}
151 
152 	domain = irq_domain_create_linear(of_fwnode_handle(node), ATH79_MISC_IRQ_COUNT,
153 				&misc_irq_domain_ops, base);
154 	if (!domain) {
155 		pr_err("Failed to add MISC irqdomain\n");
156 		return -EINVAL;
157 	}
158 
159 	ath79_misc_intc_domain_init(domain, irq);
160 	return 0;
161 }
162 
ar7100_misc_intc_of_init(struct device_node * node,struct device_node * parent)163 static int __init ar7100_misc_intc_of_init(
164 	struct device_node *node, struct device_node *parent)
165 {
166 	ath79_misc_irq_chip.irq_mask_ack = ar71xx_misc_irq_mask;
167 	return ath79_misc_intc_of_init(node, parent);
168 }
169 
170 IRQCHIP_DECLARE(ar7100_misc_intc, "qca,ar7100-misc-intc",
171 		ar7100_misc_intc_of_init);
172 
ar7240_misc_intc_of_init(struct device_node * node,struct device_node * parent)173 static int __init ar7240_misc_intc_of_init(
174 	struct device_node *node, struct device_node *parent)
175 {
176 	ath79_misc_irq_chip.irq_ack = ar724x_misc_irq_ack;
177 	return ath79_misc_intc_of_init(node, parent);
178 }
179 
180 IRQCHIP_DECLARE(ar7240_misc_intc, "qca,ar7240-misc-intc",
181 		ar7240_misc_intc_of_init);
182